Although smoking is a significant cause of damage to health and quality of life specifically for Veterans with human immunodeficiency virus (HIV), smoking cessation interventions for this population are lacking. Dr. Wilson?s proposed CDA-2 projects will develop and test a mobile health (mHealth) intervention called Mobile Contingency Management plus Evidence-Based Smoking Cessation for HIV-positive Veterans (MESH). The MESH intervention uses mHealth and telehealth technology to a) individually personalize smoking cessation counseling and pharmacotherapy, b) deliver reinforcement for smoking abstinence, and c) provide relapse- prevention messaging support. It is a personalized, tailored, multi-component intervention for smoking cessation specifically designed for Veteran smokers living with HIV. Specific aims are as follows: Aim 1: To qualitatively explore smoking cessation treatment preferences among Veteran smokers living with HIV, and to quantitively evaluate perspectives on relapse-prevention messages among Veterans and smokers living with HIV. We will complete N = 20 semi-structured interviews with VHA HIV patients (initial treatment tailoring phase) and subsequently complete N = 400 quantitative rapid online surveys (secondary user satisfaction data). Results will be used to refine design/content of the proposed intervention. Aim 2: To use a successive cohort design to develop and obtain patient feedback on an mHealth smoking cessation intervention that uses computerized algorithms to personalize treatment. We will collect qualitative data on 3 cohorts of n = 5 Veteran smokers with HIV. Results from each cohort will be iteratively used to modify the MESH treatment design/content/user experience. Aim 3: To determine the feasibility and acceptability of MESH. After finalizing design of the mHealth app, we will conduct a trial in which N = 30 Veteran smokers with HIV will be randomized to either MESH or to a comparison condition (VA Quitline and SmokefreeVET). Outcomes include feasibility of the overall approach and acceptability of the intervention. Tests of efficacy are not appropriate given power considerations and the overall focus on treatment development. Results will be used in an IIR application in Year 3 of the timeline. While the IIR design may change, I plan to propose a Hybrid Type 1 implementation-effectiveness design to test effectiveness of the MESH intervention while collecting preliminary clinic-level implementation data. Aim 4: To quantitatively examine trends and determine health disparities in use of smoking cessation aids among patients living with HIV and receiving VHA clinical care. I will leverage two large national VA cohorts to compare smoking cessation pharmacotherapy prescriptions by demographic group and medical comorbidity. I expect to detect disparities in pharmacotherapy prescription rates by medical comorbidity (e.g., pain, Hepatitis C coinfection) and demographic group (e.g., ethnicity). Results will enable future examination of whether MESH may help overcome existing disparities. This CDA-2 application is highly significant given that: 1) Smoking is prevalent among and particularly harmful for HIV-positive Veterans; 2) There is a dearth of research on smoking cessation for Veterans with HIV; 3) Current approaches to smoking cessation in this population are not efficacious; 4) As the largest U.S. provider of HIV health services, VHA is an ideal setting; and 5) The proposed intervention follows the VA Blueprint for Excellence, which prioritizes mHealth and treatment personalization to increase reach/efficacy. This CDA-2 application is innovative and unique in the following ways: 1) It is the first multi-component mHealth intervention for HIV-positive Veteran smokers that individually personalizes treatment; 2) Previous interventions have not attempted to maintain abstinence effects of behavioral reinforcement by offering relapse-prevention messaging; and 3) There is currently little knowledge of health disparities in VHA prescriptions for smoking cessation pharmacotherapy among Veterans with HIV.